Goals: Sakigake was to fly by Comet Halley as a practice mission for Japan, in preparation for the launch of Suisei, the country's primary mission to the comet.

Accomplishments: Sakigake flew by Comet Halley at a distance of about 7 million km. When ESA's Giotto spacecraft transmitted radio signals from within the comet's coma, Sakigake served as a reference vehicle, which permitted scientists to subtract the effects of Earth's atmosphere and ionosphere. The Japanese spacecraft also flew through and provided information about Earth's magnetic tail.